Conventionally, a vehicular brake device has been known, which includes a hydraulic pressure braking force generating device which generates the hydraulic pressure braking force at the vehicle wheel corresponding to the wheel cylinder by supplying thereto with the brake fluid from the master cylinder and a regeneration braking force generating device which generates a regeneration braking force at the vehicle wheel. The master cylinder of the hydraulic pressure braking force generating device is formed by an input piston which slidably moves within the master cylinder and an output piston arranged at a front side of the input piston and slidably movable within the master cylinder. The input piston is cooperatively driven by a brake operating member and the output piston is driven independently of the operation of the brake operating member, wherein the brake fluid is supplied to the wheel cylinder from the master cylinder by an advance movement of the output piston. The master cylinder is provided with a rear chamber defined by an inner periphery portion of the master cylinder, a front end portion of the input piston and a rear end portion of the output piston and a front chamber defined by the inner periphery of the master cylinder and a front end portion of the output piston. The volume of the front chamber is variable by the advance movement of the output piston. A brake fluid pathway which connects the front and the rear chambers is formed in the master cylinder so that the brake fluid in the front chamber flows into the rear chamber by the advance movement of the output piston (See Patent Literature 1).
Further, a vehicular brake control apparatus is known (See Patent Literature 2) which controls a wheel cylinder hydraulic pressure to increase in advance up to a brake preparation hydraulic pressure level before a shifting at a low vehicle speed from the regeneration braking to a hydraulic pressure braking and at the same time controls the regeneration amount to be limited by a motor if the vehicle becomes in a braking operation state when the battery charging level is equal to or more than a second value which value is lower than a first value, where the generation of the battery is stopped.